Improvement in dental pluggers



UNITED ST TES PATENT OFFIoE ANDREW JACKSON POLK, OF MIDLERSBURG,PENNSYLVANIA.

V IMPROVEMENT IN D E NTAL PLUGGERS;

.Specification forming part of Letters Patent No. 166, 139, dated July27, 1875; application filed May 15, 1875.

To all whom it may concern:

. Be it known that I, ANDREW J. POLK, of Millersburg, in the, county ofDauphin and State of Pennsylvania, have invented a new and valuableImprovement in Dentists Automatic Pluggers; and I do hereby declare thatthe following is a full, clear, and exact description of theconstruction and operation of in combining with anintermittently-reciproeating plugger-bar and its actuatingspring adevice whereby the spring may be compressed, increasing the strength ofthe stroke given to the plugger-bar according to the needs of thedentists, as will be hereinafter more fully explained and claimed.

In the annexed drawings, A designates'the tubular casing of my improveddental plugger, the same being preferably of cylindrical form, andof.any desired dimensions. In the upper end of this tube a metallic shaft,13, has its bearings, upon which a disk, 0, is rigidly secured, whichrotates through slots a cut therein, as shown in Fig. 1, and is providedwith a strip-segment, b. of eccentric form, which engages with a notch,0, cut in the upper end of an endwise-movable hammer-rod,

D, arranged in the said casing and guided in its movements therein by adiaphragm, d, through which it passes. Hammer-rod D is provided withahard-rubber head, 02, between which and diaphragm cl is arranged asuitable helical spring, S; and when the said rod is raised by theoperation of eccentric strip-cam 6, through the rotation of disk 0,spring S will be compressed, causing rod D, when released from strip b,to impart a sharp tap to an endwise-movable tool-holder, E, which isheld to its engagement with hammer-rod D by a spring, 8, recessed into adetachable nozzle,

F, andeompressed by a shoulder, 6, upon the lower end of the saidholder. Holder E is guided in its movements by means of its cylindricallower end, which fits snugly into the recess of nozzleFand by adiaphragm, f, through which its reduced upper end passes and it istubular, so that a suitable spring, 8, may be placed therein for thepurpose of holding a slide, 9, applied upon the said holder and heldagainst rotation thereon by means of a pin, h, passing into a slot cutlongitudinally therein from upward displacement, whereby a catch, Gr,pivoted at i in a second slot in the said tool-holder would be allowedto escape from its engagement with the perforated end of a pluggingtool, H; This catch is of angular form, and its power end is turnedoutwardly, so that when slide 9 is forcibly thrust upward, it willdepress the said power end, thus disengaging its other end from aperforation in the end of the plugging-tool. The shank of this tool isprismatic in form, and it fits into a correspondingly-shaped socket inthe holder, so that it is prevented from all rotation independentthereof; this rotation, when necessary for guiding the end of theplugging-tool to a tooth in different part of the mouth, being obtainedby rotating the holder itself through the medium of a milled annulus, j,on slide g, to which access is had for the purpose through a suitableopening, K, cut in the wall of the case, as shown in Fig. 2.

With a View to increasing the power of hammer-spring S to suit the wantsof the dentist under difi'erent circumstances, the upper end of the saidspring is inclosed within a sliding cap, l, in the interior of casing A,which slide is rigidly secured to a metallic plate, m, upon the outsidethereof, as shown in Fig. 2, which plate affords a fulcrum for avibrating lever,,I, the Weight end of which is adapted to hook overstripeccentric b on disk 0, and arrest its rotation when necessary; thisengagement being made automatic and positive by by means of a spring, a,rigidly secured to the under side of the power-arm of the said.leverpawl, with its free end resting upon plate m. The extreme end ofthe power-arm of pawl I is turned upward, as shown at 0, therebyaffiording a thumb-rest, whereby the dentist is afforded What I claim asnew, and desire to secure.

by Letters Patent, is-

1. The spring S, adapted to be compressed by slide Z, in combinationwith tool-holder E and hammer-rod D, substantially as specified.

' 2. The lever-pawl I, in combination with slide 1 and actuating-springS, substantially as specified.

3. The lever-pawl I and. spring n, in combination with adisk, 0, havingeccentric segmental strip 19, substantially as specified.

4. The locking-slide g, having milled annulus j. in combination with alatching-dog, G, and its retainer-spring s, substantially as specified.

5. The case A, having aperture is for operating a rotating tool holder,E, substantially as specified.

In testimony that I claim the above I have hereunto subscribed my namein the presence of two Witnesses.

ANDREW JACKSON POLK.

Witnesses:

D. W. PERRY, M. WEAVER.

